Kate O'Mara
The actor Kate O'Mara, who died on 30 March 2014 Twitter

Kate O'Mara, the English actor perhaps best known for playing Joan Collins's scheming sister Cassandra "Caress" Morrell in the 1980s US soap Dynasty, has died. She was 74.

O'Mara's agent Phil Belfield said she succumbed following a short illness in a Sussex nursing home.

Paying tribute to her talents, Belfield said: "She was extraordinary, she had so much energy and vitality with a love for theatre and acting. A shining star has gone out and Kate will be dearly missed by all who knew and have worked with her."

O'Mara had roles in Dr Who, where she played renegade Time Lord The Rani, and in Absolutely Fabulous, where she played the sister of Joanna Lumley. Older viewers probably remember her best from her starring roles in the excellent Howards' Way and the appalling Triangle – dubbed "the Dallas of the Seas".

Last year O'Mara said she would relish the opportunity to return as The Rani in Dr Who: "I'd love to come back as The Rani another time around. To have a much older woman as your adversary, there's something interesting about that."

On New Years' Eve 2012 O'Mara suffered personal tragedy when her son Dickon Young, 48, was found hanged in garages at the home they shared. He was believed to have had mental health problems since being involved in a car accident. O'Mara's other son, Chris Linde, was given up for adoption.

O'Mara's last appearance came on Benidorm in 2012. Born in Leicester to the actors John Carroll and Hazel Bainbridge, O'Mara is survived by a sister, the actor Belinda Carroll.

In her last message on Twitter on 17 March, O'Mara wrote: